WO2005115549A1

WO2005115549A1 - A protective suit

Info

Publication number: WO2005115549A1
Application number: PCT/GB2005/001997
Authority: WO
Inventors: Charles John Martin; Brian George Jones; Charles Michael Beck
Original assignee: Remploy Limited
Priority date: 2004-05-27
Filing date: 2005-05-23
Publication date: 2005-12-08
Also published as: GB0411922D0

Abstract

A protective suit system comprised of three layers of separate suits (10, 11, 13). A first layer worn next to the skin provides body heat management, a second layer provides a barrier layer to biological, chemical and/or radiological contaminants, and a third outer layer provides further barrier properties including resilience to physical wear, flame retardancy.

Description

A PROTECTIVE SUIT SYSTEM

TECHNICAL FIELD The present invention relates to a protective suit system, such as may be used by personnel in a dangerous environment contaminated by a biological, chemical or nuclear threat.

BACKGROUND ART

Protective clothing has long been used by the military in hostile contaminated environments . Such clothing may be in the form of an NBC (Nuclear Biological Chemical) suit designed to be fitted quickly, e.g. in a combat situation. Other forms of protective suits have considerably better barrier properties (e.g. may also include a self contained air supply) but need preparation time to don, and can only provide a limited period of operational activity due to physiological constraints, typically 20-30 minutes.

In recent times a need has been identified for protective suits that can be used by non-military personnel such as the police force or fire fighters. Specifically, the threat of. terrorism has lead to the requirement of metropolitan police forces to be prepared to deploy protective clothing for its personnel so the task of policing and providing order to the public can still be carried out after a terrorist attack. Perceived forms of terrorist attack include the use of biological, chemical or nuclear/radioactive weapons.

An advantage of a domestic environment is that, unlike in a war zone, there is some time (e.g. minutes after the event) to prepare clothing and then enter the contaminated area to provide aid to survivors . DISCLOSURE OF THE INVENTION

In one broad aspect of the present invention there is provided a protective suit system comprised of three layers: a first layer worn next to the skin to provide body heat management, a second layer providing a barrier layer to biological, chemical and/or radiological contaminants, and a third outer layer providing further barrier properties including resilience to physical wear.

The present invention provides a protective suit and/or a protective suit system that can be deployed primarily in a non- military situation. However, use in a military situation is also envisaged.

In a preferred form of the invention, the second layer provides a barrier to biological and/or chemical vapour, whereas the outer layer provides primary liquid chemical barrier properties and water resistance (also, preferably with a high level of fire retardancyj .

In a second broad aspect of the present invention there is provided a protective suit including seals at the wrist, ankle and face portions adapted for a tight fit with the body of the user and/or a respirator mask, said suit comprised of a „ material that is resistant to biological/chemical vapour and radiological contaminants. Preferably entry into the protective suit . is via a closable opening across a back portion of the suit. Preferably, the seals are formed from chlorobutyl rubber or equivalent material, particularly such that the face seal may stretch around a respirator mask in use.

The present invention is effectively a "protection ensemble" permeable type garment system. Whilst each layer of the system uses current and available technology, a key feature of the ensemble is the way in which incremental benefit accrues from integrating the layers together.

BRIEF DESCRIPTION OF DRAWINGS

Figure 1 is a three stage pictorial view of a protective suit system according to the present invention, Figure 2 is a three stage pictorial view of the layers of the protective suit system, Figure 3 is a front and rear view of an outer layer, Figure 4 is a front and rear view of a second layer, Figure 5 is a view of a zip fastener portion in the second layer, Figure 6 is a view of a hood portion of the second layer, and Figure 7 is a view of a wrist/ankle seal of the second layer.

MODE (S) FOR CARRYING OUT THE INVENTION

Figure 1 best illustrates the three stages for a user M to don a protective suit system according to the present invention. Firstly, the user M wears a "long John" type layer 10 that has heat management properties . An example of such a product is that produced by Outlast (registered trade mark) as a one or two piece suit. Outlast technology incorporates a waxen material into acrylic fibre to distribute and dissipate heat when the body is energetic (generating heat) and retains heat when the body or environment is cooler. In the present application such heat management is important due to the multiple layers of the complete suit system and sometimes physically demanding tasks required during operation. This first layer is hereinafter referred to as the "cooler" layer 10 for obvious reasons.

The cooler 10 preferably includes a high neck, long sleeve vest and long leg pant used as a base layer undergarment, worn directly next to the skin. It is made from a double jersey construction of modified acrylic embedded with Phase Change Materials (PCM'^"s) which alter the physical performance characteristics of the material as temperature rises and falls and as it absorbs liquid (perspiration) . The PCM process helps to dissipate body heat build up (in similar fashion to a car radiator circulating heat over a large area) and draw/wick perspiration away from the skin whilst not permitting an excessive amount of evaporation of this moisture into the rest of the protective suit system (described hereinafter) where it may be a threat to the capability of the middle carbon layer. Cooler 10 can be washed innumerable times, if necessary, to destruction. PCM technology is widely used in the sports market, however, such technology is not know in the specific field of protective clothing, particularly for Chemical, Biological, Radiological, Nuclear (CBRN) threats as in the present case.

A second layer 11 is then worn over the cooler layer 10. The main visible features of construction for layer 11 are tight fitting (butyl) rubber seals at the wrists, ankles and face. An integral hood 12 is to be coupled to a respirator mask R via the face seal. Usually, the face seal is stretched over/around the respirator mask. This second layer 11 is the key ^active' layer in the protective suit system according to the present invention and is worn directly over the cooler 10. It is a single piece hooded undercoverall in configuration made from a laminated carbon material 17 known as C-Knit and is essentially a sandwich of a single jersey polyester scrim, a polypropylene non-woven web with liquid carbon layered onto this carrier and topped by another single jersey polyester scrim. The carbon material is an adsorbent and as such has a finite functional life cycle once removed from its protective packaging. It is intended that the second layer 11 will have a "48/40" capability, ie, it will provide 48 hours cumulative protection within a 40 day out of bag' cycle. Once either of these time frames has been reached the garment is subject to mandatory replacement. Use of C-Knit, as with the cooler layer, is exclusive in this application.

A further protective membrane is stitched on the inside of the second layer suit structure, known as a Bio Layer' 16^". This is a polypropylene non-woven web integrated with a melt spun polyethylene breathable film. The role of this layer is to provide an advanced vapour/gas/particulate barrier - covering biological spore and radiological alpha-beta particulates over extended operational times .

The apertures of the second layer - wrist, ankle and facial plane - are all supported by chloro-butyl chemical proof seals that integrate with other ancillary components of the ensemble such as gloves, overboots and respirator.

A third and final "outer" layer suit 13 is worn over the second layer suit 11. The purpose of outer layer 13 is as an initial waterproof and liquid protective barrier to contaminated environments, primary level flame retardancy and to provide rugged resilience to practical operational use e.g. in some cases, operation in a disaster zone may require crawling around in debris. Layer 13 as viewed in Figure 1 shows boots 14 and gloves 15 that may also be multi-layered.

Outer layer 13 also configured as a single piece garment in the style of a hooded outercoverall . In the preferred embodiment, layer 13 is made from a meta-aramid flame retardant fibre (Nomex®) laminated with a poly-tetra-fluoro-ethylene (ptfe) membrane and the garment is trimmed with hook and eye tape adjusters at the wrists and over the frontal zip storm flap. Outer layer 13 provides a rugged barrier for general purpose activity combined with high performance flame retardant and chemical liquid proof capability. The membrane technology embedded in this layer will also provide primary scavenging capability against biological and alpha-beta particulates, thereby reducing the impact of such hazards at the bio-layer secondary level of protection (second layer 11) .

The functional properties of each layer are illustrated by Figure 2. Basic details for cooler layer 10 have been described hereinbefore, therefore, no further information is provided, however, from Figure 2 it is clear that the second layer 11 preferably has two material layers in the garment itself.

An inner (closest to the body) fabric 16 provides biological protection. In a preferred embodiment this is specified as 100% polypropylene non-woven fabric, incorporating a high- efficiency micro-fibre membrane to act as a particle filtration core layer. Such a material is available from Web Dynamics Ltd. Inner fabric 16 acts as a liner to outer fabric layer 17 that provides an adsorptive carbon layer blocking contaminant vapour. The preferred embodiment specifies a C~knit, laminated with polyester knits on both sides of a carbon barrier, supplied by Lantor Advanced Materials Group.

The best view of an assembled second layer suit 11 is given by Figure 4. Materials and preferred suppliers for the second layer are provided in the below Table- 1. Corresponding reference numerals are provided where possible.

TABLE 1

Figure 4 shows that second layer suit 11 is made from the preferred fabrics with as few joins as possible to maximise the effectiveness of the barrier to contamination. Sewing techniques known to the art are employed, to British Standard < 3870, including seam sealing on the inside (layer 16) as specified in Table 1.

User entry into layer 11 is provided at a rear opening located across the upper back area and sealed by "zip" fastener 18. An entry point in this position is preferable to a full frontal zip as would often be used for such coverall type garments . As specified in Table 1, a preferred form of slide fastener is supplied by YKK (UK) Ltd and fitted with appropriate techniques. A pull cord 20 is provided for a ^'user M to open/close fastener 19 without aid, however, it is intended that closing of the seal would be performed by a second person to ensure integrity.

Hood 12 is detailed by Figures 5 and 6. It is seen to be of three piece design with an annular (frusto-conical shaped) face seal 21 at the face opening. Seal 21 is formed of chlorobutyl rubber and stitched, then sealed to a face opening of hood 12. In prior art protective suit designs it is common for an elasticised element to be sewn into the face opening for providing "sealing" against a respirator. A resilient (stretchable) face seal as in the present invention provides improved integrity to the suit. Figure 7 shows a cuff seal at a wrist 22 or ankle 23 position, also formed from the same material and joined in the same way as face seal 21.

Chlorobutyl rubber has elastic properties while providing comparable barrier protection to the main fabrics of layer 11. As shown in Figure 1, the face seal 21 is required to stretch around a respirator mask R and maintain a seal therewith. An example of a suitable respirator is an NBC FM 12 supplied by Avon Rubber pic.

Compared with other polymers or natural rubbers, chloro-butyl has been designed to be a protection medium against aggressive chemical attack. This material has been chosen for the protective suit of the present invention in conjunction with other ancillary products to enable a closure that appears to be the most secure option presently available. One of the features of the compound is that when it connects with other items manufactured from the same material it creates a ^Λclam' effect. For example, the facial plane seal around the second layer hood is designed to integrate with the respirator facial plate (the respirator mask is also manufactured from chlorobutyl) . When the seal and respirator connect, an "opposite poles attraction" type adhesion is achieved that flams' the two butyl components together very firmly. This is a major advantage when designing a system to deny ingress to liquid, vapour, gas and particulate.

There does not appear to be any other permeable CBRN protection suit that uses this technology. The essence of this statement is the word ^λpermeable' . The second layer 11, constructed in the manner and from components specified, is unique in the field of safety garments and can be used without and independently of the outer layer 13 in many situations.

The manufacturing techniques for outer layer 13 are to the same standard as second layer 11. Preferred materials and suppliers are specified in Table 2 below. Reference numerals are provided where possible.

TABLE 2

REFERENCE COMPONENT DESCRIPTION and Supplier NUMERAL 24 Main Fabric "Nomex" f lameblocker, tri-laminate . 100% Aramid-PTFE membrane-100% aramid W L Gore and Associates Seam Sealing Tape 100% aramid, 22mm wide Hotmelt adhesive W L Gore and Associates 25 Front Slide Fastener Metal slide fastener (zip) 6mm "Nomex" tape Kroko Fasteners Slider (zip) for X-form two way, oxidised finish above Kroko Fasteners Pull cord for slider Cord, braided nylon width 9mm Textile Enterprises Ltd

26 Leg hem slide Metal slide fastener fastener (zip) 6mm closed end, "Nomex" tape Kroko Fasteners Slider (zip) for Oxidised finish above Kroko Fasteners

27 Hood and Trouser Hem 19mm wide, Black elastic M. Wright

Outer layer 13 provides a rugged cover for layer 11 and some resistant properties. It does not have (in this embodiment) air tight sealing at the wrist, ankle and face portions. An elastic hem 27 is provided for basic closure or with a Velcro (registered trade mark) fastener for adjustability (seen in Figure 3) .

Outer layer 13 has a front conventional zip closure 25 contrasting with the rear upper back closure 18 of the second layer 11. The position of the respective zips is noteworthy because the second layer 11 presents a solid frontal plane adjacent the outer layer 13 zip and thereby minimises points of possible vapour and gas ingress. The arrangement complicates a contaminant entry path. In other words, the suit system would be less effective if the user entry points were in alignment (e.g. both zips 25 and 18 at the front) .

For ease of fit, e.g. over boots, zip fasteners 26 with a placket are provided at the lower leg portions in the known way.

Figure 3 also shows various pockets 29 sewn to the outer layer garment 13 for carrying accessories that may be required.

In addition to water, resilience, outer layer 13 also has flame retardant qualities for broadened operational uses . For certain applications (e.g. fire fighting) such flame retardant qualities could be upgraded. As in the case of layer 11, outer layer 13 may be used on its own for very mildly contaminated environments or merely for its water resistant qualities. It can fit over normal combat fatigues or civilian clothes if necessary.

Finally, in use as a complete system, boots 14 and gloves 15 are donned to seal with chlorobutyl seals 22 and 23. Available boot and glove designs can be used with the protection suit system of the present invention, e.g. NBC Lightweight Overboots from Acton International, Inc. made from butyl rubber provide the desirable characteristics.

An inner and outer glove 15 may be used, e.g. a "coolmax" liner glove and CB Moulded Glove for NBC use, both supplied by Acton International, Inc.

Additional binding may be used to ensure a good seal with wrists 22 / ankles 23 of layer 11.

The protective suit system and particularly second layer suit by itself, is a functional product applicable to both military, police and civil use. It is intended to provide up to a few hours exposure time in dangerous environments dependent on the level of contamination. The system is found to be lighter, more flexible and more comfortable to wear over long periods than existing NBC type protection.

The three layer suit system also benefits from launderable characteristics, e.g. the base "Cooler" layer may be washed many times, the second and outer layers can be expected to be washed up to 6 times without detriment to their performance. It is stressed that this laundering is for the removal of conventional soiling only, and does not constitute a decontamination process . Collectively, the protective suit of the present invention provides (from the outside inward) flame retardency, liquid chemical barrier, vapour, gas, biological and radiological particulate barrier CBRN capability with a heat management, physiological stress" reduction comfort layer. This collective capability is unique in CBRN product terms .

Incrementally, the system adds to the performance factors inherent in each individual layer. A synergy between the layering occurs as each adds a support function to the other. In isolation, the materials provide a specified capability in their own right. By combining this particular arrangement of materials there is a bonus capability developed by virtue of the fact that each layer - whilst particularly dedicated to its own essential function - will aid the barrier protection of all the cumulative layers, eg, the Nomex outer shell will provide not only its specified liquid and flame protection, it will also assist in the protection against particulate spores and certain vaporous contaminants. This benefit could be considered a somewhat "unexpected result" but was an advantage deliberately sought during development of the present invention, ie, it is not accidental, it is a contrived feature of the development process not present in the prior art.

Whilst designed as ah integrated, layered system, the protective suit of the present invention can be deployed as individual layers according to tactical choice by the end-user. End-user choice is an operational deployment decision once the nature of the contaminant being dealt with is known, but the system has been designed with this option in mind. Whereas the present invention provides extensive across the board protection in an unknown hazard environment, the criticality of protection can be judged more finitely once the first responder has knowledge of the exact nature of threat. For example, rhe second layer 11 could be selected by a firefighter to give vapour/gas/particulate protection but worn as part of general turn-out gear rather than in conjunction with the other layers if the fireman is in a hazard zone that does not include liquid chemical challenge; The outer layer 13 may be worn as a policeman's ^,battle-wear' over his conventional clothing if the nature of the hazard does not include any vaporous/gaseous/particulate threat but maybe more oriented around, say, firebomb protection where flame and liquid chemical protection are more important.

Deployment methodology is a fundamental part of the philosophy behind the present invention and the resulting system is unique in the art.

INDUSTRIAL APPLICABILITY

As described, the present invention can generally be constructed from materials and techniques known in the manufacture of protective clothing. Novelty lies in the synergistic combination of the materials and layers .

It should be clear that the broad specifications including materials and preferred suppliers may be substituted with equivalents still falling within the general scope of the invention, particularly as materials science improves over time .

Claims

A protective suit system comprised of three layers: a first layer worn next to the skin to provide body heat management, a second layer providing a barrier layer to biological, chemical and/or radiological contaminants, and a third outer layer providing further barrier properties including resilience to physical wear.

The protective suit system according to claim 1 wherein the three layers are separate suits to be donned by the user in sequence.

3. The protective suit system according to claim 1 or 2 wherein the second layer provides a barrier to biological and/or chemical vapour.

4. The protective suit system according to any one of the preceding claims wherein the outer layer provides primary liquid chemical barrier properties and water resistance.

5. The protective suit system according to any one of the preceding claims wherein the outer layer exhibits flame retardancy.

6. The protective suit system according to any one of the preceding claims wherein the first layer is embedded with Phase Change Materials (PCM's).

The protective suit system according to claim 2 wherein the second layer suit has an entry point for the user out of alignment with an entry point to the third layer suit.

8. The protective suit system according to claim 7 wherein the entry point in the second layer is across the back of the second layer and the entry point in the third layer is down the front of the third layer.

9. The protective suit system according to any one of the preceding claims wherein the first layer is made from Outlast material or equivalent.

10. The protective suit system according to any one of the preceding claims wherein the second layer includes a laminated carbon material made from a sandwich of a single jersey polyester scrim, a polypropylene non-woven web with liquid carbon layered onto this carrier and topped by another single ersey polyester scrim.

11. The protective suit system according to claim 10 wherein the second layer includes a further protective membrane adhered on the inside of the laminated carbon material, comprised of a polypropylene non-woven web integrated with a melt spun polyethylene breathable film.

12. A protective suit including seals at the wrist, ankle and face portions adapted for a tight fit with the <body of the user and/or a respirator mask, said suit comprised of a material that is resistant to biological/chemical vapour and radiological contaminants .

13. A protective suit according to claim 12 comprised of a laminated carbon material made from a sandwich of a single jersey polyester scrim, a polypropylene non-woven web with liquid carbon layered onto this carrier and topped by another single jersey polyester scrim.

14. The protective suit according to claim 13 including a further protective membrane adhered on the inside of the laminated carbon material, comprised of a polypropylene non-woven web integrated with a melt spun polyethylene breathable film.

15. The protective suit according to any one of claims 12 to 14 wherein entry into the protective suit is via a closable opening across a back portion of the suit.

16. The protective suit according to any one of claims 12 to 15 wherein the seals are made from chlorobutyl rubber or equivalent material.